Go-EventSourcing-CQRS VS elastic

Source code you can find in GitHub repository The main idea of this project is the implementation of Event Sourcing and CQRS using Go, EventStoreDB, gRPC, MongoDB and ElasticSearch. Didn't write in this article about Event Sourcing and CQRS patterns, because it makes the article huge and the best place to read is [microservices.io (https://microservices.io/patterns/data/cqrs.html), found this article is very good too, and highly recommend Alexey Zimarev "Hands-on Domain-Driven Design with .NET Core" book and also his blog.

i am trying to generate the following query using github.com/olivere/elastic/v7

I think that https://olivere.github.io/elastic/ is a lot better as an API client

For Go available two good libraries for elasticsearch, the official Elasticsearch client and another one from community olivere elastic, both is good, but at this moment only the official client supports 8 version of elasticsearch and for serious production think it's the choice.

You are using the Query DSL, which is documented here, and has examples for boolean combination queries, so if you want it built up in a more strongly-typed fashion, check the documentation for it: https://github.com/olivere/elastic/wiki/QueryDSL

ElasticSearch repository implementation uses go-elasticsearch official library, another good one is olivere elastic but here it's not support 8 version which used for this project.

In this project we have microservice working with EventStoreDB using oficial go client, for [projections (https://zimarev.com/blog/event-sourcing/projections/) used MongoDB and Elasticsearch for search, and communicate by gRPC and REST. Did not implement here any interesting business logic and didn't cover tests, because don't have enough time, the events list is very simple: create a new order, update shopping cart, pay, submit, cancel, change the delivery address, complete order, and of course in real-world better use more concrete and meaningfully events, but the target here is to show the idea and how it works. Event Sourcing can be implemented in different ways, used here EventStoreDB, but we can do it with PostgreSQL and Kafka for example. After trying both approaches, found EventStoreDB is a better solution because all required features are implemented out of the box, it is optimized and really very good engineers developing it.

Relevant Discussion from the maintainer

I have only used the olivere library and I think it is as good as a Go library gets.